1. Field of the Invention
The present invention relates generally to a wireless sensor network, and more particularly to an apparatus and method for providing security of data packets that are transmitted and received among sensor nodes of the wireless sensor network.
2. Description of the Related Art
In general, wireless sensor network technology enables an autonomous network including a plurality of sensor nodes that perform a computing function and a wireless communication function. The plurality of sensor nodes transmit and receive sensed information acquired through the wireless sensor network. It is also possible to perform remote control or monitoring through the network.
In such a wireless sensor network, a sensor node transmits information sensed by a sensor to a sink node, and the sink node transmits the received information to a base station that serves as a gateway. Also, the base station transfers the sensed information to a user that is to receive the information through a network.
Because a wireless sensor network includes sensor nodes that are powered by small batteries that are basically non-exchangeable, the respective sensor nodes can only transmit/receive data depending on the given life span of the batteries. Accordingly, it is preferable to reduce the amount of energy that is consumed when data is transmitted and received among the sensor nodes. From this viewpoint, protocols for sensor network environments, which are independent for respective layers, have been proposed, and as a primary study, energy-efficient protocols in Medium Access Control (MAC) layers and network layers of the sensor network have been proposed. Also, energy-efficient protocols in an ad-hoc sensor network, which operates according to the ad-hoc dispersed structure of the wireless sensor network, have been proposed.
In the sensor network, security suites for data security are preset when data packets for transmitting and receiving data among the sensor nodes are generated, and data, to which the preset security suites have been adapted, are transmitted and received. The security suites, after being initially set as described above, are continuously used when the sensor nodes transmit and receive the data.
According to the conventional wireless sensor network as described above, data is transmitted and received among the sensor nodes using the preset security suites, regardless of network characteristics, application characteristics, and control characteristics. Consequently, energy consumption involving the preset security suites in unnecessarily high.
For example, if the wireless sensor network characteristic is a public network characteristic that does not require the security function, this network is not required to set the data security suites among the sensor nodes. However, according to the conventional wireless sensor network, the data is transmitted and received through the setting of the data security suites, even in the public network characteristic, and thus unnecessary energy consumption occurs.
Also, in the conventional wireless sensor network, a fixed security level is always provided during data transmission and reception, and thus, an unnecessarily excessive security function is provided.